Locomotive control installation



Jan. 8, 1929.

T. E. CLARK ET AL LOCOMQTIVE CONTROL IHSTALLATION 5 Filed Dec. 13, 1926 2 Sheets-Sheet l zgnz HuVEISIZIRZAMf ATTORNEY Jan. 8, 1929.

\ T. E. CLARK ET AL LOCOMOTIVE CONTROL INSTALLATION Filed Dec. 13, 1926 Q a 2, Sheets-Sheet 2 00 T INVENTOR I 6mm ZTORNEY Patented Jan. 8, 1929,

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THOMAS E. CLARK AND CLARK, OF DETROIT, MICHIGAN, ASSIGNORS TO CONTINUOUS TRAIN CONTROL CORPORATION, OFiDETiROIT, MICHIGAN, A COB- PORATION OF MICHIGAN.

LOCOMOTIVE CONTROL INSTALLATION.

Application filed December 13, 1928. Serial No. 154,419.

This invention relates to the construction of automatic brake-controlling apparatus for locomotives of railways whose trackway is divided into blocks and equipped, in whole or in part, with controlling stations adapted to impress radio-frequency currents of either of two wave lengths upon the rails, according to the occupancy of the track ahead, and.

to impress both such currents upon the rails at points where the controlled track joins non-controlled track.

This construction is of the same general character as that shown in our pending application Serial Number 125,907, filed July 5 30, 1926, but embodies additions thereto and modifications thereof which insure the application of the brakes should any material part of the present application fail for any reason.

In the accompanying drawings, Fig. 1 is a diagram of the electric circuits and instrumentalities connected thereto of a locomotive installation embodying the present invention and F ig. 2 is adiagram similar to Fig. 1, showing the positions of the parts when the locomotive is running on a trackway which is not equipped with control installations. Similar reference characters refer to like parts in both views.

The two receptor coils 1 and 2 and the circuits connected thereto are designed to develop potential by reason of electro-magnetic flux or force at the rails of a controlled track which will usually be divided into blocks provided with instrumentalities at their exit ends to impress radio-frequency currents upon the rails, the frequency of such currents being variable accordingto the condition of the blocks of track in advance, depending on occupancy, broken rails or open switches, the arrangements and construction of such current transmitting devices being such that current of one frequency will be impressed when the block in advance is unoccupied, and a current of another frequency when the block in advance is occupied, but no current being present in that portion of an occupied block between the occupying obstacle and the entrance end of such block. In

the present construction, the coil 1 and the spond to the train control current which is present in a block when the next block in advance is unoccupied and will be termed the clear circuit, while the coil and its circuits connected thereto are intended to recuits respond to current when such block in mas 9.

advance is occupied, and will be termed the cautlon circult. Receptor electron tubes '3 7 and 4 and operating tubes 5 and 6 are connected into'the circuits of these coils and these operating tubes control the opening and closing of electric circuits and relays connected therein to govern the automatic operatlon of the air brakes of the locomotive or other vehicle equippedwith the present in stallation. Y a

The receptor coils 1 and 2 are preferably mounted on the leading truck of the locomotive near the rails so as to pass through the energized fields of greatest electromagnetic flux around the rails, and the filament circuits of the tubes 3 to 6, inclusive include loops which entend down to and around these collector coils so that should either be torn from its mounting, the circuit of the tube filament-s will be broken. This circuit is over wires 7 and 8, relay 9, wires'lO, 12, 13, 14 and 15, filament of tube 3, wire v17, filament oftube 5, wire 18, filament of tube 6, wire 19, filament of tube 4, wire 20, main return wire 21 and wire 22.

The plate current is derived from a transformer or from the dynamotor 24 which is energized by current derived from the generator G over wires 726 and 2721. The wire 30 connects to the primary windings 31 of transformers .32 and 33 andthen to the plates of tubes 3 and 4. Wires 34 and 35 extend from the wire 30 tolrelays 36 and37- 53, 54, and 56. The wire 53-connects to the grid of the electron tube 3 and the wire 56 to the grid of the tube 4 while the wires 54 and 55 adjustably connect to the resistance 42 which connects to the negative end of the resistance 57 by means of wire 58. As the currents in these receptor coil circuits are usually weak, the electron tubes shown are made use of. If the current in these receptor coil I r the eeecnd.

circuits were sufficiently strong l tubes 5 and might be dispeiiise rnents and the plates of the In order i that all instruinentalities of this installation may-move to neutral'or danger position should any breakage or failure occur,

provisions are so made that the control relays '36Iand 3'7 will function only when proper "the cores of the tr:-insforn1ers'32 and 33 from becoming saturated.

"The resistance -57 connects to the positive side of thedynaniotorhy means of wire j andis preferably ofabout 5000 ohms, much greater than that of resistances 42, 45 and 4:7' combined. It therefore so influences resistance42 that this may be considered asan ex- ',t(-3l'lSlOIl of thenegative end thereof in relathrough the resistances 12, 4:5 so

I tubes 3 tion tothe filaments. The plates of the four tubes also connect to the positive wire 30 as "above described, and these plates are thereferepositive relative to the filaments of'these tubes which connect-to the negative wire 4C8 and 47.

A negative bias of potei'itiai is impressed upon the grid of tube 3 by reason of the wire 54 engaging the'resistance {l2 on the negative side-of the'filament connection all, the circuit to this grid being over'thiswire 54:, receptor "coil "'1 and wire 53. "Similarly, t he circuitto thegridof tube l consistsof the wire 55 engaging resistance 42, coil 2 and wire 56. An electro-niagnetic flux around the track rail is responded to by-areceptor circuit and an alternatingpotential-is built up in the receptor circuit which alternates at the frequency to which this receptor circuit is tuned' This alternating potential acts on the grids of and ltovcause theni tobe first less negative and then more negative and this "action causes the current in the plate circuit to increase and decrease in unison withthe frequency impressed on the grid circuit. 550

long as direct constant current passes from filamentto plate 1n tubes 3 and l, no current is induced in the secondary windings and 61,-but when a potential is induced in the receptor circuit 1'- changes the bias on the grid of tube 3 or l; the current passing from filament to plate of such tubes isincreased and decreased, resulting in an alternating current being induced in the proper secondary winding.

Negative bias is also present in the gridsof tubes 5 and 6, this bias of the former being derivedfrom the connection e6 between the resistances 45 and 47, while that of the tube 6' is derived fronrthe connection 43 between resistances 42 and 4'5. So long as this bias continues constant in'tube 5, its plate current.

the gridcircuits of tubes 5 and the secondary windings 60 and 61fburn-out,

:is somewhat obstructed, but whenever the current is varied in the plate circuit of tube 3, induced alternating current is set up in the esecond-arywinding 60 of transformer 32, the

responds to oscillating current in the circuit of receptor coil=2.

. The usual grid leaks 63 are connected into 6, so that, if

the negative bias of potential referred to 'above is'not affected thereby. Condensers] 64::are POSltlOIlBLlWhGIGVGl" necessary, to by- ,pass andconfin'e the radio-frequency cur-rents to "their proper circuits. A by-pass condenser 65".bri'dg es' between the inain positive wire 30-and negative wire 48 and-a condenser 67 bypasses the resistance 57. Small "switches 65 may be installed wherever-desirable=to afford an opportunity for the use of current ineters. A wavetrap 66 may be connected into each of thereceptor coil circuitsto eliini .nate interference from any electro-magnetic' waves excepting those for which that particular receptor circuit is tuned. 1

In thefollowing description, whenever an armature is specified, item be denoted by a small letter together with the reference-nu-' meral of its relay.

Then receptor-coil 1 intercepts electromagnetic *flux of proper ffrequency, current ffroin the plate of tube 5 energizes relay 36, and whencoil'EZintercepts properflun, relay 37 is energized. When neither receptorcoil intercepts'fiui; for which-its circuit is tuned, neither of these control relays is energized andtheir armatures' are in dropped position. Fig. '1 shows the positions ofthc several .arinatu-reswhile control relay 36 is energized,

which is while the locomotive is proceeding under clear track conditions. In tracing the several circuits, wires*8 and 21'inay be taken as the positive and negative wires respectively. The control relay 36 when energized, closes the circuit to the niain"clear relay 74Jfroin wire'8 over wires and '71, pneumatically controlled switch72, wire 73, n1ain,clear relay 74, wire 75, armature 36 and wires 76and 77 to negative wire 21. If control relay 37 were energized, current would pass through main caution relay 78 from wire 7 3 and then over wire 79, armature 37 and wires 76 and 7 7 to wireQl.

Three electric signal lamps 80, 81 and 82 are mounted in the locomotive cab, being and red respectively,

preferablygreen, yellow danger,

to indicate clear, caution and ,andithese lampshave acommon wire-83 con- "nectedtow1re'8. The return clrcuit of green lamp 80 is over wire'84, dropped armature 78, wire 85, and armature i'l to wire 21. This lamp therefore receives current only energized.

An electro-pneumatic valve 90, of well known construction and commonly known as valve, 18 adapted to cause reduction an E. P. of the air pressure within the control valve '89 of the brake system, and within the casing of this E. P. valve is a magnet 91 adapted to draw down its armature 92 from which a stem extends down to the valve 9 1, which is held on its seat while the magnet 91 is energized. I

The construction and operation of this E. P. valve and of the control valve is fully described and claimed in application Serial Number 153,258, filedby William L. Coop and Charles B. tone on December 8th, 1926, but the connection between thatconstruction and the present control system should be sketched briefly.

When a train is to be moved under clear conditions,.at which time the E. P. valve is energized, the engineer swings the handle of this train valve to permit air to fill the brake pipe and thus release the brakes. This causes a slow accumulation'of pressure within the chamber 97, which is'connected to the train pipe, and through the passage 99 into the top of the cylinder 100 above the piston 101. V

This brake pipe pressure is less than the pressure within the main reservoir (not shownlto which a pipe 106 connects. Air

from the main reservoir flows into the cylinder 107 through this pipe 106 and through a passage into the chamber 126. The piston 109 in the cylinder 107 connects to the valve 111. I

The piston 101' is attached to a valve stem 118 which carries a valve 119, which normally is closed. A second cylinder 121 adjacent and preferably in alinement with the cylinder 100 contains a piston 122, normally held upward. This cylinder is formed with any desired number and type of openings 12s.- and the lower end of the stem 125 which connects to the piston 122 is attached to the switch member 72 which connects the wires 71 and 75 when in the position shown.

"When the magnet 91 of the E. P. valve is deenergize'd, air pressure in the chamber 126 lifts the valve 94 and permits air to flow from the cylinder 107 to the pipe whistle 132 which sounds to indicate that this valve is deenergized.

Normally, the pressure in the cylinder 107 is that of the main air reservoir and in the chamber 97 is that of the train pipe, which is lower than that in the cylinder 107.- When the E. P. valve is (lo-energized and air flows from the cylinder 107, the greater pressure in the chamber 97 forces the piston 109 to the right in Fig. 1, cutting off the connection between the train pipe and the cylinder 100 and permitting air to flow from cylinder 100.

The reduction of the pressure in the cybinder 100 above the piston 101 requires a pre determined time interval beforethe pressure below this piston lifts the pistonfand the valve 119 c0nn'ected thereto. This time interval is provided to permit the E41 valve-to bereenergized to forestall the application of'the brakes, as will be explained later on. Should the E. P. valve remain ale-energized beyond this predetermined time interval, the piston 101 and valve 119 will lift, and the train pipe air will rush down onto piston 122 in cylinder 121, forcing down this piston below the holes 124 which will permit the free discharge of the train line air. When this piston is forced down, the switch 72 is opened, and with it the circuit of wires 71 and 73. Switch 72 remains open until'the pressure in the train pipe is so reduced that the piston 122 is no longer held down by the pressure above it. As this air switch is completelyenclosed, it cannot be closed manually.

. Referring now to 1, it will be noticed that the normal energizing circuit of the E. P. valve includes wire 8, wire 70, switch wire 146, magnet 91, wire 147, armature 9, wire 1 18, dropped armature 78, Wire 14.9, armature 74*, wire 150, forestalling and held closed by relay 9 which is energized so long only as the receptor coils 1 and 2 are in operative position and all the filamentjcircuits of the electron tubes are unbroken. So long, therefore, as all the parts are in good condition and the control relay 36 is energized, the E. P. valve will remain energized.

The position of the several parts when receptor coil 2 and its circuit cause the energization of control relay 37, is shown in Fig. 2. Current flows over common wire 83 .to yellow lamp 81 and over wire 152, armature 78 wire 153, dropped armature 74, wire 1541, dropped armature 161", wire 155, starting key 156, wires 157 and 158, dropped armature 74 and wires 21 and 22. This lamp 81 therefore receives currentso long as relay 78 is ener gized and relay 74 is de-energized. As soon as relay 78 is energized, its lifted armature 78 opens the circuit of the E. valve, and unless this circuit is restored or another is made for the E. P'. valve before the piston 101 lifts, the brakes will be applied. A forestalling circuit is established by momentarily depressing the forestalling key 151 which closes the circuit consisting of Wires 8, and 71, switch 72, wire 73, holding relay 160, wire 159, armature 74", wire 163, depressed key 151, and wires 21' and 22' served that this circuit cannot be made if the operation of the key has been delayed until switch 72 has been moved down by train pipe pressure. The energized relay160, which is slow releasing, attracts its armature a and closes a circuit from this relay over wire 159, armature 160 wires 164, 14-8 and 167, armature 160, wire 155, key 156, wires 157, and

key 151: wires 21 and22, and that this circuit is i It will be obi being lifted by 158, armature is energized while relay 161 is de-energized.

When no current is picked up, both relays are energized, as will be explained later on.

The new circuit for the E. P. valve com prises wire 1 17, armature 9 ,-wires.148 and 167, armature 160, wires 168 and 155, key 156, wires 157 and 158, dropped armature 7 1 and wires 21 and 22. This circuit will re main'closed-i-io long as the holding circuit is ken-t closed until opened by armature 74 its relay which would result in the first described normally energized circuit being closer I i If no current is present in either relay 36 or 37, all the armatures oi' relays 7 1, 78, 166 and 161 will be in dropped position and cur rent will pass to the red lamp 82 and thence over wire 170, armature 78 wire 153, armature 74;, wire 15 1, armature 161", wire 155, key 156, wires 157 and 158 and armature 74; to wire 21. The energizing circuit of the E. P. valve is opened by armature 7 1 drop ping.

The key 156 is preferably so placed at some point on'the locomotive that it can be reached only by a person standing on the ground which necessitates the locomotive being brought to a stop when the red lamp receives current which occurs when the locomotive enters an occupied block when neither of the two control relays is energized. When this key is depressed, current passes from wire 73 to relay 161 and over wire 171, key 156, wires 157 and 158 and dropped armature 7 1 to wire 21, energizing relay 161 and closing: a stick circuit therefor over wire 171, armature 161, wires 17 2 and 173, dropped armature 78 wire 166, dropped armature 74, wire 150 and key 151 to wire 21. Key 156 is now released and moves to normal position. Ener gized relay 161 now closes a circuit for the E. P. valve over wire 1 17, armature 9, wire 1 18, armature 161, wire 155, key 156, wire 158 and dropped armature 7 1 to wire 21. The brakes which were automatically appliedwhen the locomotive entered the occupied block may now be released by the engineer and the locomotive may now proceed. hen no current is received by either receptor occurs under danger, conditions, the E. P. valve causes the piston 122 to open the switch 7 2 which causes the brakesto be applied and the train to come to a stop, which it must always do when this switch opens. The switch remains open until the train pipe pressure falls so'low that thespring under piston 122 can lift this switch. After this switch is opened the depression of key 151 has no effect. Neither has it any efiect when both relays 7 a and 78 arede-energized. But after this switchis closed the key 156 may be depressed and the engineer may release thebrakes.

74 and wires'21 and 27. The

coil, which.

At such'points where the locomotive passes from a controlled section of track to one not controlled, means are provlcled tor snnulta- I wires 8, and 71, switch 72, wire 73, relay 161, wires 171 and 1741, armature 74", wire 163,

depressed key 151 and wire 21. Energized relay 161 raises its armature a and as soon as key 1511s released, closes a stick circuit over wire 171 armature 161" wires 172 and 173 armature 78 wire 1 19, armature 7 1 wire 150 and key 151 to wlre 21. It also closes a circuit for the E. PJValVB comprising wire 147,

armature 9 wire 1 18, armature 161, wire 155,key 156, armature 7 8, wire and armature 74 to wire 21. The stick circuit and the circuit for the P. valve will remain closed until the locomotive again passes onto con: trolled trackway. 7

- The starting key '156will also be used when the locomotive is to be started in around house, being depressed after the generatorG 241- have reached their usual output to complete a cirand dynamotor speed and current cuit for the E. P. valve which, when energized, permits charging of the main air res ervoir. The red lamp .82 receives current until the key 156is depressed and thus indi cates that relay 161 has not closed the circuit of the E. P. valve. But as soon as relay 161 is energized, its armature 7) opens the circuit to this lamp. As the locomotive is notconnected to a train, the train pipe and chamber 97 have no pressure.

Should either oi? the receptor coils be broken or any one of the filaments of the tube become inoperative, no plate current will pass to the relays 36-37 and the circuits controlled thereby will become inoperative to carry current to the E. P. valve. Failure of the transformers 32 and 33 or of any of the circuits controlled by the relays 86 and 37, or of the generator or dynamotor will havev the same effect. I i

It will be noticed that the wire 10 extends fromwire 18 which connects the filaments of the tubes to the wire 41 and that the breaking of any one of these wires will open all the plate circuits and render relays 86 and 87 inoperative. The circuit between wire 11 and the dynamotor includes the resistances 42, 14, 15 and 17 and the wires43, 4 1, 16 and 48, so that should there be a break at any point in this circuit, the plate current of all the tubes will fail. Vacuum tubes 3 and 41 are biased to that potential which gives the maximum amplification for the st le tube used. This potential determined r1y selecting-that point the bias potentials.

grid voltage plate current curve of the tube Where the tube operates on the straight part of the curve. To save the use of high current through the tube it is advisable to normally work on that part of the straight line which is on the negative grid potential of the center line. This will give. a stand-by of from 6 to 9 mills in a type PR 10A tube. I

In practice the proper potential is found by placing the tubes in their respective Cir-- This does not necessarily mean that'the grid of this tube has been made positive.

' Current will flow when'the negative potential on the grid is decreased and the amount of current that will flow is governed by the style of tube used and the resistance in this plate circuit.

Resistance 57 is connected with resistances 4-2, 5 and l? through Wire 58 to constitute a resistor w ich is connected across the high voltage terminals of the dynamotor 24 and the grid bias for the various tubes is obtained bv takin ta )8 oil" from this resistor at oints that give the proper potential for the most ellicient operation of the tubes.

This combination of resistances is used to ob" in both the plate current and the grid The positive feed to the various plate circuits is taken of? from Wire and the negative plate connection to the filaments is taken off at wire 18 which connects to the end oi resistance 42. This point 42 is the negative plate current connection to the filament and the positive current connection for the various grid circuits. The various grid potentials areobtained by moving from the connection of wire 18 with resistance 42 toward the negative terminal of the dynamotor. It will be seen that the negative return for the plate current is through the resistance 42 over 43, wire 44, resistance 45, wire 46, resistance 47 to the negative terminal of the dynamotor and should this circuit be broken at any point in the circuitthe negative plate connection will be broken and'no current will flow in the plate circuit of the various tubes. The system shown and described may therefore be said to be biased on the side of safety.

.The details of construction and the proportions or" the parts of this locomotive installation may all be changed by those skilled in the art without departing from the spirit of our invention as set forth in the following claims. I

We claim 1. In combination with a current source, a pair of electromagnetic elements an electron tube for each electro-i'nagn etic element and embodying a plate electrically connected to such element, a filament for each tube connected'to tween the tron tube for each of the first nam means to establish negative bias of potential on the grids of the several tubes, receptor coils adapted to'receive oscillatingcurrents electric circuit connecting said coils to the grids of the receptor tubes, and a, circuit be;

plate and filament, a receptor electween the current source andthe filaments of said tub-es including loopsextending" around both of said receptor'coi'ls.

2. In combination with a current.

ed tubes,

source, a

said current source and a grid 'bepair of electro-magnetic elements, an ampli-,j-

vtying electron tube for each electro-magnetic' element and embodying a platefelectricaliy connected to such tube connected to said current source and a grid between the plate and filament,a're

element, a filament for each I ceptor electron tube for each of saidv first" named tubes, means to establish negative bias of potential in the grids of thefseveral tubes,

receptor coils adapted to receive oscillating currents, electric circuits connecting said coils to the grids of the receptor tubes, and a wave trap connected'into each of said receptor coil circuits to block interit'erence'by the -electro-magnetic waves for. Which'the other receptor coil circuit is tuned.

In combination with acurrent source,

a train-control valve adapted to be held closed by current from said source, a whistle connected to said valve and adapted to sound when said valve is open, circuits between said current source and said valve, receptors for radio-frequency currents and instrumentalities controlled therby for opening and closing said circuits, said instrumentalities embodying electron tubes relays and circuits between the tubes and relays, erable key adapted to act in conjunction with the iiistrumentalities controlled by one of said receptors to close one of said circuits, and an air switch controlled by said valve and adapted to open the circuits between it and the current source after the valve has been opened a predetermined length of time. 4. In combination with a current source, a pair of relays connected thereto, an electron tube for each relay embodying a plate connected to the relay, a resistance circuit embodying a series of resistances and connections to both poles connection between the filaments of said tubes and said resitsance circuit, and connections extending from the grids of said tubes to said normally produce a negative bias of potential in'the grids.

a manually op-- of the current source, a

5. In combination with a current source, a

pair of relays and circuits connecting one pole'of each to the current source, an amplify ingelectron tube for each relay embodying a plateconnected to the other pole of the relay,

a complete resistance circuit embodying resistances 1n series and connect ons to the current source, receptor electron tubes and transformers connectedto the plate circuits thereof, a connection between the filaments of by curent fromsa d said tubes and said resistance circuit, secondary windings of said transformers con nected to the grids of saidfirst named tubes,

from the grids .of all connections extending tance .circult on the said tubes .to sald i negative side thereof relativeto the filament connection sov asto normally produce a negative bias vof potential in the grids, and receptor coils ,and to the gridsof said receptor tubes.

k6..In combination with a mar-rent source, a

traimcontrol valveadaptedito be held closed source, a CLlCLlltbGliYVQQIl thecurrent source and said valve, a'. l6i eptor for high-frequency current andv instrumentalitiesi controlled thereby for closing; said circuit, a secondcircuit between the current sition,

' sourceandi sa d valve, a, forestallingkey in' said circuit, asecond receptor for high-freuency' current and instrumentalities con trolled thereby for closingsaid second circuit when said key ismoved to circuit-closingiposaid key and the instrumentalities controlled its armatures andsaid valve, key and current source-Whlch errcu tsare closed when both a third :ci icri be w e t e c rre t source and said vaLve, adapted to be closed by by both'of said receptors, and an -eleotromagnetic switch icontrolled by said valve for opening theenergizing circuit of said valve;

should a predetermined time elapse between the opening of said valve and the closing of said key. 1

,7. In combination with a current source, a the armatures thereof, a current source, a train-control valve normally held closed by current from V 'forestalling key and circuits between the currentsource and said valve whereby currentwill flow to said valve when one vof. said relays isenergized,and when the ,key 'is actuated and the secondrelay is ,en

ergized, a third relay and circuits between the-first named relays are deenergized andthe keyis actuated, an eleetro-pneumatic switch controlled by said valve for opening the energiaing circuit of said valve shoulda pre- 5 determined time-elapse between thelopening v of said valve and the clos ng of sald key, and e a fourth relay and circuits between its armatures and sald valve, key and current source which circuits are closed when both the first named relays areenergizedand thekey isac- I tuated.

THOMA C BK- f CLARK. 

